$sort_col = $_GET['sort_id'];
                                                              $listing_sql .= ' order by ';
                                                              switch ($sort_col) {
                                                                  case 'high':
                                                                      $listing_sql .= "products_price desc ";
                                                                      break;
                                                                  case 'low':
                                                                      $listing_sql .= "products_price asc ";
                                                                      break;
                                                                  case 'title':
                                                                      $listing_sql .= "pd.products_name ";
                                                                      break;
                                                                  default:
                                                                      case 'sortorder':
                                                                          $listing_sql .= "p.pSortOrder ";
                                                                          break;
                                                                  default:
                                                                      $listing_sql .= "p.pSortOrder ";
                                                                      break;
                                                              } //switch ($sort_col)